text: Cook batted for 836 minutes in Abu Dhabi for his 263 - the third-longest innings by time in Test history, and the longest ever by an Englishman.
  Joe Root made 85 and Ben Stokes hit 57 as Pakistan's bowlers toiled.
  With two wickets remaining and England's first-innings lead slim, a draw remains the most likely result.
  Cook eventually fell to off-spinner Shoaib Malik - himself a double centurion in the match - when he was caught at short fine leg sweeping.
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  The 30-year-old began the day on 168 and might have been dismissed only five runs later, when he inside-edged a delivery from Imran Khan and wicketkeeper Sarfraz Ahmed dropped a difficult chance.
  But thereafter the England skipper combined superbly with Root in a morning of trouble-free accumulation.
  He moved to his double hundred - the third of his Test career, drawing him level with Kevin Pietersen - with a clip behind square off Wahab Riaz.
  Root was eventually dismissed after lunch when he chased a wide delivery from Rahat Ali, but Cook's formidable powers of concentration proved greater.
  Playing with immense discipline - he hit only three boundaries all day - the captain amassed the highest score by an English batsman overseas since Wally Hammond hit 336 against New Zealand in 1933.
  He survived a fiery spell of reverse-swing bowling from Wahab Riaz - which accounted for Jonny Bairstow, trapped LBW for 8.
  And he might even have been able to overtake his own career best of 294 - set against India at Edgbaston in 2010 - if the umpire had spotted that Malik appeared to overstep in delivering the wicket-taking ball.
  Root said Cook was "knackered" after his mammoth innings.
  "He's played out his skin," he added. "It takes concentration and skill to bat for that long.
  "We're thrilled for him and it's given us a chance of a result."
  Former England batsman Geoffrey Boycott said Cook's innings displayed "patience and determination".
  "He just went along serenely," he said. "It was a splendid innings of everything that's needed to bat."
  Ex-England captain Michael Vaughan praised Cook's "art and talent of concentration".
  He said: "Ball by ball, over by over. He keeps it very simple. It was low-risk cricket in a routine that he has honed over many years of playing, delivered in that kind of heat and pressure.
  "I'd put him with Geoffrey Boycott in terms of concentration, which is the biggest strength an opening batsman needs."
  It was another tough day for the bowlers on a pitch that has offered precious little assistance.
  And just as in England's innings, it was the spinners who bore the brunt of the batting-friendly conditions.
  After England's Moeen Ali and Adil Rashid went for 0-121 and 0-163 respectively in the first innings of the match, Pakistan's Zulfiqar Babar became the third bowler of the match to concede a century of runs without taking a wicket.
  It was part-timer Malik who made the first breakthrough for spin in the match when he bowled Stokes - with spinners having bowled 170.1 wicketless overs for 565 runs prior to that point.
  Zulfiqar was into his 69th over - within sight of the world record for wicketless overs in an innings, which stands at 72 - when he induced Jos Buttler to loft a drive into the hands of Asad Shafiq at deep cover.
target: A superb double century from captain Alastair Cook saw England to 569-8, a lead of 46 runs, at the end of day four of the first Test against Pakistan.